An immunohistochemical study on the distribution of endocrine cells in the digestive tract of gray goose (Anser anser)

The objective of this study was to investigate the morphology and the distribution of 5- hydroxytryptamine (5- HT), somatostatin (SS), gastrin (Gas), glucagon (Glu), and substance P immunoreactive (IR) cells in the digestive tract of gray goose by the immunohistochemical streptavidin-peroxidase method. The samples were taken from 10 healthy adult gray geese. The results showed that 5 kinds of IR cells were mainly distributed between the mucous epithelium and intestinal gland. Th e number of 5-HT-IR cells was highest in the rectum and duodenum, but none were observed in the pylorus. SS-IR cells appeared in great numbers in the pylorus, duodenum, and cecum; however, they were not found in esophagus. Gas-IR cells were mainly distributed in the glandular stomach and jejunum. Glu-IR cells appeared in small numbers in the glandular stomach, duodenum, and jejunum, but were not detected in other tissues. Substance P-IR cells were located in the jejunum, cecum, and rectum. Analysis of the present study showed that the distribution and morphological features of these 5 different endocrine cells were related to the feeding habits and metabolism in the digestive tract of the gray goose.